Wednesday, October 23, 2013

Terrafugia TF-X: The Real Flying Car

Terrafugia, the Woburn,
MA, company developing the
Transition flying car, has plans for a vertical take-off and landing (VTOL) sibling.
The proposed Terrafugia TF-X would be a tilt-rotor flying machine that would
take off and land like a helicopter. Instead of a runway, the TF-X could use a
helipad or parking lot. That’s important because Terrafugia’s devices aren’t so
much flying cars as roadable aircraft that take you from the airport to your
destination a few miles away. The closer you land to your destination, the
better. Don’t sell your Cessna 400 just yet. The flying car is a decade away
and will likely cost on the high side of a half-million dollars. Maybe a
million.

The Terrafugia flying car is a small fuselage with four road
wheels on the bottom, along with stubby wings with electrically driven rotors
that point vertically for liftoff, then rotate horizontally for level flight.
The transition from vertical to horizontal flight is tricky in a VTOL plane.
Terrafugia says the TF-X electronics manage that, as well as the rest of the
flight. In other words, the pilot decides when to lift off - and how high -
before starting to fly horizontally, and the plane actually manages those
orders. That’s not unusual; some military aircraft wouldn’t fly without
computers controlling stability.

Propulsion appears to be a gas turbine for horizontal flight
and hybrid electric for ground travel. For liftoff and landing, the rotors
would be turned electrically via a generator and battery storage, as would the
road wheels.

Same concept as the Osprey tilt-wing

The real flying car appears to work much like the Marine
Corps V-22 Osprey, which is good news because the technology now works, the
defense department says, and bad news because early Ospreys crashed a lot and
the project ran over budget. Thirty years after the concept Osprey project
kicked off, the Marine Corps now says its fleet has half the accident rate of
other Marine aircraft. (The Marines have most of the 140 or so Ospreys
deployed.) The Osprey carries 24-32 soldiers at a cost of about $70 million,
about twice as much as the cost of a helicopter with the same payload.